archy/packages/app/server/claude-proxy.ts

import { spawn } from 'child_process'
import { createServer } from 'http'
import { readFileSync, existsSync } from 'fs'
import { resolve, dirname } from 'path'
import { fileURLToPath } from 'url'

const __dirname = dirname(fileURLToPath(import.meta.url))

// Load .env.local from workspace root (monorepo) or cwd
function loadEnv() {
  for (const base of [resolve(__dirname, '../../..'), process.cwd()]) {
    const path = resolve(base, '.env.local')
    if (existsSync(path)) {
      try {
        const buf = readFileSync(path, 'utf8')
        for (const line of buf.split('\n')) {
          const m = line.match(/^([^#=]+)=(.*)$/)
          if (m) {
            const key = m[1].trim()
            const val = m[2].trim().replace(/^["']|["']$/g, '')
            if (!process.env[key]) process.env[key] = val
          }
        }
        break
      } catch {
        /* ignore */
      }
    }
  }
}
loadEnv()

const PORT = 3141
const CLAUDE_BIN = resolve(process.env.HOME ?? '', '.local/bin/claude')
const APP_URL = process.env.APP_URL ?? 'http://localhost:5173'

/** API key (sk-ant-api03-...) or OAuth token (sk-ant-oat...) from Max subscription */
function getAnthropicCredential(): string | undefined {
  const fromEnv = process.env.ANTHROPIC_API_KEY
    ?? process.env.VITE_ANTHROPIC_API_KEY
    ?? process.env.ANTHROPIC_TOKEN
    ?? process.env.VITE_ANTHROPIC_TOKEN
  if (fromEnv) return fromEnv
  const home = process.env.HOME ?? ''
  const settingsPath = resolve(home, '.claude/settings.json')
  if (home && existsSync(settingsPath)) {
    try {
      const json = JSON.parse(readFileSync(settingsPath, 'utf8'))
      const env = json?.env
      if (env && typeof env === 'object') {
        const t = env.ANTHROPIC_TOKEN ?? env.VITE_ANTHROPIC_TOKEN ?? env.ANTHROPIC_API_KEY ?? env.VITE_ANTHROPIC_API_KEY
        if (typeof t === 'string') return t
      }
    } catch { /* ignore */ }
  }
  return undefined
}

const ANTHROPIC_CREDENTIAL = getAnthropicCredential()
const isOAuthToken = (s: string) => /^sk-ant-oat/.test(s)

const SEARCH_WEB_TOOL = {
  name: 'search_web',
  description: 'Search the web for current information. Use this when the user asks for news, recent events, facts you are unsure about, or any information that may have changed. Perform one search per distinct topic. Returns titles, URLs, and snippets.',
  input_schema: {
    type: 'object',
    properties: {
      query: {
        type: 'string',
        description: 'Search query (e.g. "Bitcoin price March 2025", "latest news AI regulation")',
      },
    },
    required: ['query'],
  },
}

function mapModelToApi(model: string): string {
  if (model?.includes('opus')) return 'claude-opus-4-20250514'
  if (model?.includes('haiku')) return 'claude-3-5-haiku-20241022'
  return 'claude-sonnet-4-20250514'
}

async function runSearchWeb(query: string): Promise<string> {
  const url = `${APP_URL.replace(/\/$/, '')}/api/web-search?${new URLSearchParams({ q: query })}`
  try {
    const res = await fetch(url, {
      headers: { Accept: 'application/json' },
      signal: AbortSignal.timeout(10000),
    })
    if (!res.ok) return `Search failed: ${res.status}`
    const data = (await res.json()) as { results?: { title?: string; url?: string; content?: string }[] }
    const results = data.results ?? []
    if (results.length === 0) return 'No results found.'
    return results
      .map((r, i) => `${i + 1}. [${r.title ?? 'Unknown'}](${r.url ?? ''})${r.content ? ` — ${r.content.slice(0, 150)}${r.content.length > 150 ? '…' : ''}` : ''}`)
      .join('\n')
  } catch (err) {
    return `Search error: ${err instanceof Error ? err.message : String(err)}`
  }
}

async function streamViaAnthropicApi(
  model: string,
  system: string | undefined,
  messages: { role: string; content: string }[],
  res: import('http').ServerResponse,
): Promise<void> {
  const apiModel = mapModelToApi(model)
  const apiMessages = messages.map((m) => ({
    role: m.role === 'assistant' ? 'assistant' : 'user',
    content: typeof m.content === 'string' ? m.content : JSON.stringify(m.content),
  }))

  let clientDisconnected = false
  res.on('close', () => { clientDisconnected = true })

  const sendDelta = (text: string) => {
    if (!clientDisconnected) {
      res.write(`data: ${JSON.stringify({ type: 'content_block_delta', delta: { type: 'text_delta', text } })}\n\n`)
    }
  }

  const sendError = (msg: string) => {
    if (!clientDisconnected) {
      res.write(`data: ${JSON.stringify({ type: 'error', error: { message: msg } })}\n\n`)
    }
  }

  let turnMessages = [...apiMessages]
  const maxToolRounds = 5
  let rounds = 0

  while (rounds < maxToolRounds) {
    rounds++
    const body: Record<string, unknown> = {
      model: apiModel,
      max_tokens: 4096,
      system,
      messages: turnMessages,
      tools: [SEARCH_WEB_TOOL],
    }

    const headers: Record<string, string> = {
      'Content-Type': 'application/json',
      'anthropic-version': '2023-06-01',
    }
    if (isOAuthToken(ANTHROPIC_CREDENTIAL!)) {
      headers['Authorization'] = `Bearer ${ANTHROPIC_CREDENTIAL}`
      headers['anthropic-beta'] = 'oauth-2025-04-20'
    } else {
      headers['x-api-key'] = ANTHROPIC_CREDENTIAL!
    }

    const apiRes = await fetch('https://api.anthropic.com/v1/messages', {
      method: 'POST',
      headers,
      body: JSON.stringify(body),
      signal: AbortSignal.timeout(120000),
    })

    if (!apiRes.ok) {
      const errBody = await apiRes.text()
      sendError(`Anthropic API ${apiRes.status}: ${errBody.slice(0, 200)}`)
      break
    }

    const data = (await apiRes.json()) as {
      content?: { type: string; text?: string; id?: string; name?: string; input?: { query?: string } }[]
      stop_reason?: string
    }

    const content = data.content ?? []
    const toolUses = content.filter((b) => b.type === 'tool_use')
    const textBlocks = content.filter((b) => b.type === 'text')

    if (data.stop_reason === 'tool_use' && toolUses.length > 0) {
      const toolResults: { type: string; tool_use_id: string; content: string }[] = []
      for (const tu of toolUses) {
        if (tu.name === 'search_web' && tu.id && tu.input?.query) {
          console.log('[proxy] tool search_web:', tu.input.query)
          const result = await runSearchWeb(tu.input.query)
          toolResults.push({ type: 'tool_result', tool_use_id: tu.id, content: result })
        }
      }
      turnMessages = [
        ...turnMessages,
        { role: 'assistant' as const, content },
        { role: 'user' as const, content: toolResults },
      ]
      continue
    }

    for (const block of textBlocks) {
      if (block.text) sendDelta(block.text)
    }
    break
  }

  if (!clientDisconnected) {
    res.write('data: [DONE]\n\n')
    res.end()
  }
}

const server = createServer((req, res) => {
  if (req.method === 'OPTIONS') {
    res.writeHead(204, {
      'Access-Control-Allow-Origin': '*',
      'Access-Control-Allow-Methods': 'POST, OPTIONS',
      'Access-Control-Allow-Headers': 'Content-Type',
    })
    res.end()
    return
  }

  if (req.method !== 'POST' || req.url !== '/v1/messages') {
    res.writeHead(404, { 'Content-Type': 'application/json' })
    res.end(JSON.stringify({ error: 'Not found' }))
    return
  }

  let body = ''
  req.on('data', (chunk) => { body += chunk })
  req.on('end', () => {
    try {
      const payload = JSON.parse(body)
      const { model, messages, system, webSearch } = payload

      const useTools = webSearch === true && !!ANTHROPIC_CREDENTIAL

      if (useTools) {
        res.writeHead(200, {
          'Content-Type': 'text/event-stream',
          'Cache-Control': 'no-cache',
          'Connection': 'keep-alive',
          'Access-Control-Allow-Origin': '*',
          'X-Accel-Buffering': 'no',
        })
        streamViaAnthropicApi(model, system, messages ?? [], res)
        return
      }

      if (webSearch === true && !ANTHROPIC_CREDENTIAL) {
        console.log('[proxy] webSearch: using CLI built-in WebSearch + pre-fetched context')
      }

      const modelFlag = model?.includes('opus') ? 'opus'
        : model?.includes('haiku') ? 'haiku'
        : 'sonnet'

      const history = (messages ?? []) as { role: string; content: string }[]
      const userMessages = history.filter((m) => m.role === 'user')
      const lastUserMsg = userMessages[userMessages.length - 1]?.content ?? ''

      const contextParts: string[] = []
      if (system) contextParts.push(system)
      const prior = history.slice(0, -1)
      if (prior.length > 0) {
        contextParts.push(
          'Conversation so far:\n' +
          prior.map((m) => `${m.role}: ${m.content}`).join('\n')
        )
      }

      const systemPrompt = contextParts.length > 0 ? contextParts.join('\n\n') : undefined

      const args = ['-p', '--model', modelFlag]
      if (systemPrompt) args.push('--system-prompt', systemPrompt)
      if (webSearch === true) {
        args.push('--allowed-tools', 'WebSearch', 'WebFetch')
        args.push('--permission-mode', 'dontAsk')
      }
      args.push('--', lastUserMsg)

      console.log(`[proxy] → claude -p --model ${modelFlag}${webSearch ? ' [WebSearch]' : ''} "${lastUserMsg.slice(0, 60)}..."`)

      const procEnv = { ...process.env, NO_COLOR: '1', TERM: 'dumb' }
      if (webSearch === true) {
        delete procEnv.DISALLOWED_TOOLS
      }
      const proc = spawn(CLAUDE_BIN, args, {
        stdio: ['pipe', 'pipe', 'pipe'],
        env: procEnv,
        detached: false,
      })

      proc.stdin.end('')

      res.writeHead(200, {
        'Content-Type': 'text/event-stream',
        'Cache-Control': 'no-cache',
        'Connection': 'keep-alive',
        'Access-Control-Allow-Origin': '*',
        'X-Accel-Buffering': 'no',
      })

      let fullOutput = ''
      let clientDisconnected = false

      proc.stdout.on('data', (chunk: Buffer) => {
        const text = chunk.toString()
        fullOutput += text
        console.log(`[proxy] stdout +${text.length}b total=${fullOutput.length}b`)

        if (!clientDisconnected) {
          const sseData = {
            type: 'content_block_delta',
            delta: { type: 'text_delta', text },
          }
          res.write(`data: ${JSON.stringify(sseData)}\n\n`)
        }
      })

      proc.stderr.on('data', (chunk: Buffer) => {
        const msg = chunk.toString().trim()
        if (msg) console.error('[proxy] stderr:', msg)
      })

      proc.on('error', (err) => {
        console.error('[proxy] spawn error:', err)
        if (!clientDisconnected) {
          const errData = {
            type: 'error',
            error: { message: `Spawn error: ${err.message}` },
          }
          res.write(`data: ${JSON.stringify(errData)}\n\n`)
          res.write('data: [DONE]\n\n')
          res.end()
        }
      })

      proc.on('close', (code, signal) => {
        console.log(`[proxy] ← exit code=${code} signal=${signal} output=${fullOutput.length}b`)
        if (!clientDisconnected) {
          res.write('data: [DONE]\n\n')
          res.end()
        }
      })

      res.on('close', () => {
        clientDisconnected = true
        if (proc.exitCode === null && !proc.killed) {
          console.log('[proxy] Client disconnected, killing process')
          proc.kill('SIGTERM')
        }
      })

    } catch (err) {
      console.error('[proxy] Parse error:', err)
      res.writeHead(400, {
        'Content-Type': 'application/json',
        'Access-Control-Allow-Origin': '*',
      })
      res.end(JSON.stringify({ error: String(err) }))
    }
  })
})

server.listen(PORT, () => {
  console.log(`\n  Claude proxy → http://localhost:${PORT}`)
  console.log(`  Binary: ${CLAUDE_BIN}`)
  if (ANTHROPIC_CREDENTIAL) {
    const mode = isOAuthToken(ANTHROPIC_CREDENTIAL) ? 'OAuth (Max)' : 'API key'
    console.log(`  Tool use (search_web): enabled (${mode})\n`)
  } else {
    console.log(`  Tool use: add ANTHROPIC_TOKEN (Max) or ANTHROPIC_API_KEY to .env.local\n`)
  }
})